Biosynthesis of collagen during the life cycle of human diploid cell lines.

In the course of the active phase of growth collagen synthesis appears relatively stable and decreases when the culture passes into the degenerative phase III. The increase of cell nitrogen indicates the increasing accumulation of cell proteins with their aging in vitro. The ratio of soluble to insoluble collagen is relatively constant in fibroblast cultures from different tissues, periods of development during the active phase of growth. The increase of insoluble collagen in long term cultivated Marfan syndrome fibroblasts indicates the possible relationship between increasing stability of collagen and ageing of fibroblasts in vitro. Further studies confirmed the significant differences between control fibroblast and fibroblast derived from tissues of patients affected by Marfan syndrome. No differences were found in collagen synthesis and in the ratio of soluble to insoluble collagen in fibroblast strains from embryos, foetuses, children and young adults. The collagen synthesis and the ratio of soluble to insoluble collagen does not differ in fibroblast cultures derived from or post-natal period of life. The collagen synthesis in amniotic fluid cells was confirmed by analysis of cell proteins and proteins produced into the cultivation medium. The ultrastructural analysis of these cells reveals formation of intracellular fibrills and their growth in the extracellular space. The possibility of prenatal investigation of inborn errors of collagen metabolism is pointed out.